MySQL 9.0.0
Source Code Documentation
ha_blackhole.h
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23
24#include <sys/types.h>
25
26#include "my_base.h"
27#include "my_inttypes.h"
28#include "sql/handler.h" /* handler */
29#include "sql/key.h"
30#include "sql/table.h" /* TABLE_SHARE */
31#include "thr_lock.h" /* THR_LOCK */
32
33class String;
34class THD;
35struct FT_INFO;
36namespace dd {
37class Table;
38}
39
40/*
41 Shared structure for correct LOCK operation
42*/
47 char table_name[1];
48};
49
50/*
51 Class definition for the blackhole storage engine
52 "Dumbest named feature ever"
53*/
54class ha_blackhole : public handler {
55 THR_LOCK_DATA lock; /* MySQL lock */
57
58 public:
59 ha_blackhole(handlerton *hton, TABLE_SHARE *table_arg);
60 ~ha_blackhole() override = default;
61 /* The name that will be used for display purposes */
62 const char *table_type() const override { return "BLACKHOLE"; }
64 return HA_KEY_ALG_BTREE;
65 }
66 bool is_index_algorithm_supported(enum ha_key_alg key_alg) const override {
67 return key_alg == HA_KEY_ALG_BTREE || key_alg == HA_KEY_ALG_RTREE;
68 }
69 ulonglong table_flags() const override {
74 }
75 ulong index_flags(uint inx, uint, bool) const override {
76 return ((table_share->key_info[inx].algorithm == HA_KEY_ALG_FULLTEXT)
77 ? 0
80 }
81 /* The following defines can be increased if necessary */
82#define BLACKHOLE_MAX_KEY 64 /* Max allowed keys */
83#define BLACKHOLE_MAX_KEY_SEG 16 /* Max segments for key */
84#define BLACKHOLE_MAX_KEY_LENGTH 3072 /* Keep compatible with innoDB */
85 uint max_supported_keys() const override { return BLACKHOLE_MAX_KEY; }
86 uint max_supported_key_length() const override {
88 }
90 [[maybe_unused]]) const override {
92 }
93 int open(const char *name, int mode, uint test_if_locked,
94 const dd::Table *table_def) override;
95 int close(void) override;
96 int rnd_init(bool scan) override;
97 int rnd_next(uchar *buf) override;
98 int rnd_pos(uchar *buf, uchar *pos) override;
99 int index_read_map(uchar *buf, const uchar *key, key_part_map keypart_map,
100 enum ha_rkey_function find_flag) override;
101 int index_read_idx_map(uchar *buf, uint idx, const uchar *key,
102 key_part_map keypart_map,
103 enum ha_rkey_function find_flag) override;
105 key_part_map keypart_map) override;
106 int index_next(uchar *buf) override;
107 int index_prev(uchar *buf) override;
108 int index_first(uchar *buf) override;
109 int index_last(uchar *buf) override;
110 void position(const uchar *record) override;
111 int info(uint flag) override;
112 int external_lock(THD *thd, int lock_type) override;
113 int create(const char *name, TABLE *table_arg, HA_CREATE_INFO *create_info,
114 dd::Table *table_def) override;
116 enum thr_lock_type lock_type) override;
117 FT_INFO *ft_init_ext(uint flags, uint inx, String *key) override;
118 int ft_init() override;
119
120 protected:
121 int ft_read(uchar *buf) override;
122
123 private:
124 int write_row(uchar *buf) override;
125 int update_row(const uchar *old_data, uchar *new_data) override;
126 int delete_row(const uchar *buf) override;
127};
app_data_ptr new_data(u_int n, char *val, cons_type consensus)
Using this class is fraught with peril, and you need to be very careful when doing so.
Definition: sql_string.h:167
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_lexer_thd.h:36
Definition: table.h:47
Definition: ha_blackhole.h:54
bool is_index_algorithm_supported(enum ha_key_alg key_alg) const override
Check if SE supports specific key algorithm.
Definition: ha_blackhole.h:66
int index_read_map(uchar *buf, const uchar *key, key_part_map keypart_map, enum ha_rkey_function find_flag) override
Positions an index cursor to the index specified in the handle ('active_index').
Definition: ha_blackhole.cc:195
int index_prev(uchar *buf) override
Definition: ha_blackhole.cc:237
int external_lock(THD *thd, int lock_type) override
Is not invoked for non-transactional temporary tables.
Definition: ha_blackhole.cc:158
int rnd_next(uchar *buf) override
Definition: ha_blackhole.cc:128
int open(const char *name, int mode, uint test_if_locked, const dd::Table *table_def) override
Definition: ha_blackhole.cc:84
ulong index_flags(uint inx, uint, bool) const override
Definition: ha_blackhole.h:75
int ft_read(uchar *buf) override
Definition: ha_blackhole.cc:276
~ha_blackhole() override=default
int index_read_idx_map(uchar *buf, uint idx, const uchar *key, key_part_map keypart_map, enum ha_rkey_function find_flag) override
Positions an index cursor to the index specified in argument.
Definition: ha_blackhole.cc:207
int info(uint flag) override
General method to gather info from handler.
Definition: ha_blackhole.cc:150
st_blackhole_share * share
Definition: ha_blackhole.h:56
int write_row(uchar *buf) override
Write a row.
Definition: ha_blackhole.cc:104
void position(const uchar *record) override
Definition: ha_blackhole.cc:145
ulonglong table_flags() const override
Definition: ha_blackhole.h:69
int index_next(uchar *buf) override
Definition: ha_blackhole.cc:230
FT_INFO * ft_init_ext(uint flags, uint inx, String *key) override
Definition: ha_blackhole.cc:258
int close(void) override
Definition: ha_blackhole.cc:93
uint max_supported_key_length() const override
Definition: ha_blackhole.h:86
int delete_row(const uchar *buf) override
Definition: ha_blackhole.cc:116
THR_LOCK_DATA ** store_lock(THD *thd, THR_LOCK_DATA **to, enum thr_lock_type lock_type) override
Is not invoked for non-transactional temporary tables.
Definition: ha_blackhole.cc:163
const char * table_type() const override
The following can be called without an open handler.
Definition: ha_blackhole.h:62
int ft_init() override
Definition: ha_blackhole.cc:274
int index_first(uchar *buf) override
Definition: ha_blackhole.cc:244
THR_LOCK_DATA lock
Definition: ha_blackhole.h:55
uint max_supported_keys() const override
Definition: ha_blackhole.h:85
ha_blackhole(handlerton *hton, TABLE_SHARE *table_arg)
Definition: ha_blackhole.cc:81
int rnd_init(bool scan) override
rnd_init() can be called two times without rnd_end() in between (it only makes sense if scan=1).
Definition: ha_blackhole.cc:123
int index_last(uchar *buf) override
Definition: ha_blackhole.cc:251
int create(const char *name, TABLE *table_arg, HA_CREATE_INFO *create_info, dd::Table *table_def) override
Create table (implementation).
Definition: ha_blackhole.cc:99
uint max_supported_key_part_length(HA_CREATE_INFO *create_info) const override
Definition: ha_blackhole.h:89
int rnd_pos(uchar *buf, uchar *pos) override
Definition: ha_blackhole.cc:139
int index_read_last_map(uchar *buf, const uchar *key, key_part_map keypart_map) override
The following functions works like index_read, but it find the last row with the current key value or...
Definition: ha_blackhole.cc:219
enum ha_key_alg get_default_index_algorithm() const override
Get default key algorithm for SE.
Definition: ha_blackhole.h:63
int update_row(const uchar *old_data, uchar *new_data) override
Update a single row.
Definition: ha_blackhole.cc:109
The handler class is the interface for dynamically loadable storage engines.
Definition: handler.h:4573
TABLE_SHARE * table_share
Definition: handler.h:4581
A table definition from the master.
Definition: rpl_utility.h:249
#define BLACKHOLE_MAX_KEY
Definition: ha_blackhole.h:82
#define BLACKHOLE_MAX_KEY_LENGTH
Definition: ha_blackhole.h:84
static int flags[50]
Definition: hp_test1.cc:40
static int flag
Definition: hp_test1.cc:40
This file includes constants used by all storage engines.
ha_key_alg
Definition: my_base.h:98
@ HA_KEY_ALG_RTREE
Definition: my_base.h:109
@ HA_KEY_ALG_BTREE
Definition: my_base.h:108
@ HA_KEY_ALG_FULLTEXT
Definition: my_base.h:111
ha_rkey_function
Definition: my_base.h:78
ulong key_part_map
Definition: my_base.h:1008
Some integer typedefs for easier portability.
unsigned long long int ulonglong
Definition: my_inttypes.h:56
unsigned char uchar
Definition: my_inttypes.h:52
static int record
Definition: mysqltest.cc:195
Definition: buf0block_hint.cc:30
The version of the current data dictionary table definitions.
Definition: dictionary_client.h:43
mode
Definition: file_handle.h:61
required string key
Definition: replication_asynchronous_connection_failover.proto:60
#define HA_BINLOG_ROW_CAPABLE
Definition: handler.h:347
#define HA_FILE_BASED
Definition: handler.h:332
#define HA_CAN_INDEX_BLOBS
Definition: handler.h:265
#define HA_READ_NEXT
Definition: handler.h:534
#define HA_KEYREAD_ONLY
Definition: handler.h:579
#define HA_READ_OUT_OF_SYNC
Definition: handler.h:432
#define HA_CAN_GEOMETRY
Definition: handler.h:236
#define HA_CAN_FULLTEXT
Definition: handler.h:313
#define HA_BINLOG_STMT_CAPABLE
Definition: handler.h:348
#define HA_CAN_SQL_HANDLER
Definition: handler.h:318
#define HA_READ_ORDER
Definition: handler.h:550
#define HA_READ_RANGE
Definition: handler.h:557
#define HA_AUTO_PART_KEY
Definition: handler.h:270
#define HA_NULL_IN_KEY
Definition: handler.h:253
#define HA_READ_PREV
Definition: handler.h:538
case opt name
Definition: sslopt-case.h:29
Definition: ft_global.h:72
Struct to hold information about the table that should be created.
Definition: handler.h:3202
This structure is shared between different table objects.
Definition: table.h:701
KEY * key_info
Definition: table.h:751
Definition: table.h:1407
Definition: thr_lock.h:124
Definition: thr_lock.h:139
handlerton is a singleton structure - one instance per storage engine - to provide access to storage ...
Definition: handler.h:2734
Definition: ha_blackhole.h:43
uint table_name_length
Definition: ha_blackhole.h:46
char table_name[1]
Definition: ha_blackhole.h:47
uint use_count
Definition: ha_blackhole.h:45
THR_LOCK lock
Definition: ha_blackhole.h:44
thr_lock_type
Definition: thr_lock.h:51